Calibration method and calibration system
By combining the projection unit and the camera unit, the projection position of the vehicle projection system is automatically calibrated, solving the problem of high costs associated with manual calibration and achieving efficient and accurate projection calibration.
Patent Information
- Application Number
- CN202480037381.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-07-31
- Filing Date
- 2024-07-16
- Publication Date
- 2026-01-02
AI Technical Summary
In existing technologies, the calibration of vehicle projection systems requires manual adjustment, resulting in high costs and expenses.
The test image and test strip are projected by the projection unit, and the reflected brightness is detected by the camera unit. The projection position is automatically calibrated by the control unit and the limiting unit, thus realizing automated projection surface calibration.
It enables automated calibration of the projection system, reducing time and cost while improving calibration accuracy and clarity.
Smart Images
Figure CN121264036A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a calibration method having the features of independent claim 1 and a calibration system having the features of independent claim 9. Background Technology
[0002] Currently, an increasing number of vehicles equipped with projection systems are entering mass production. In these vehicles, the projectors are manually adjusted within the factory production range to ensure that the projection is aligned with an optimized surface. Here, the position and angle of the projector are adjusted using mechanical adjustment screws, thereby adapting the projected image to the surface.
[0003] Manually adjusting the desired position of the projection is vehicle-specific and therefore time-consuming and consequently costly in the factory process. Summary of the Invention
[0004] Therefore, the object of the present invention is to overcome at least partially one of the aforementioned disadvantages. In particular, the object of the present invention is to provide a calibration method that is simple, calibrates the position of the projection with reduced costs, and is also cost-effective.
[0005] The aforementioned task is solved by the calibration method having the features of independent claim 1 and the calibration system having the features of independent claim 9. Further features and details of the invention arise from the dependent claims, the description, and the drawings. The features and details described herein in conjunction with the calibration method according to the invention naturally also apply in conjunction with the calibration system according to the invention, and vice versa, so that the disclosure of each aspect of the invention is always referred to or may be referred to mutually.
[0006] The first aspect of the present invention is a calibration method for calibrating the projection of an image sequence from a projection unit of a motor vehicle onto a target surface of a motor vehicle's dashboard, comprising the following steps:
[0007] -Execute the first test sequence using the following steps:
[0008] - At least two, preferably at least three, more preferably at least four first test images are projected onto the projection surface of the dashboard by means of a projection unit, wherein two first test images are projected onto the projection surface in full, wherein the first test images are projected sequentially, and wherein each test image is assigned a brightness.
[0009] - During the execution of the first test sequence, the first reflection of each first test image projected into the interior space of the motor vehicle is detected by means of a camera unit.
[0010] -The maximum brightness in the internal space in one of the first reflections is determined by the calculation unit of the control unit, and the maximum brightness is assigned to the brightness of one of the first test images for use as the brightness in the second test sequence.
[0011] -Execute the second test sequence using the following steps:
[0012] - At least two, preferably at least three, more preferably at least four test bars with different widths are projected onto the projection surface of the dashboard by means of a projection unit, wherein the test bars are projected sequentially;
[0013] - During the second test sequence, the second reflection of each test strip projected into the interior space of the motor vehicle is detected by means of a camera unit;
[0014] - The minimum brightness in the internal space of one of the second reflections is determined by the calculation unit of the control unit, and the minimum brightness is assigned to the strip width of one of the test strips to be used as the strip width for determining the target surface boundary.
[0015] - Determine at least one target surface boundary of the target surface through the following steps:
[0016] - At least two, preferably at least three, more preferably at least four second test images are projected onto a projection surface using a projection unit, wherein the second test images are projected sequentially, and each second test image has a strip of a certain width in its edge region, which has a minimum brightness of second reflection.
[0017] -The third reflection of the second test image in the interior space is detected by means of a camera unit.
[0018] -If the camera unit detects a third reflection, then the target surface boundary is determined by the acquisition unit of the control unit.
[0019] - By means of the limiting unit of the control unit, the second test image of the projection unit is limited to at least one target surface boundary of the target surface in order to perform the calibration of the target surface.
[0020] Brightness is understood here as the intensity of light that can be generated by projection or reflection. The brightness of the first test image is the light intensity of the test image, whether emitted or projected. Brightness can be related to the color of the test image or a definite change in the brightness of the illumination source of the projection unit, i.e., the dimming process of the illumination source of the projection unit.
[0021] Therefore, the execution of the first test sequence, that is, the projection of the first test image, can be implemented with test images of different colors.
[0022] The first test image is then projected in full onto the projection surface of the vehicle's dashboard. The camera unit then detects the first reflections of the first test image projected into the interior space of the vehicle, i.e., the reflections of the brightness or color of the first test image through interior materials such as seat covers or steering wheel.
[0023] The first reflection, also known as residual radiation reflected from the interior, occurs on a surface different from the vehicle's interior space—the projection surface on which the projection unit projects the test image. In other words, the first reflection is measured within the vehicle's interior area, and is not directly illuminated by the projection unit.
[0024] Therefore, the calculation unit calculates the maximum brightness of the first reflection of the light reflected from the interior space, that is, the test image projected onto the interior space of the motor vehicle.
[0025] Maximum brightness is used to select the brightness, and thus the optimal brightness setting of the illumination source for the projection unit and / or the color of the first test image.
[0026] As described above, a test image with maximum brightness in the internal space will be used to perform the second test sequence.
[0027] The brightness or maximum brightness of the first test image is then used for test strips with different widths. The width of the test strips is gradually reduced until the light intensity of the test strips is so low that the camera unit can only detect darkness, i.e., no longer detects a second reflection.
[0028] The test strip width (where the minimum brightness, i.e., minimum light intensity) is calculated, which is also the width of the test strip (at which the camera unit can just detect the second reflection) and then used to determine the target surface boundary.
[0029] The minimum brightness value here is also understood as the following threshold, which is related to the bar width, where the threshold represents the following minimum bar width, which can also be detected as a reflection in the internal space by means of a camera unit.
[0030] Not only the first test sequence but also the second test sequence here are vehicle-specific and are primarily influenced by the corresponding interior trim and its reflections. For example, light-colored (e.g., white, cream, or tan) materials, linings, covers, or plastics of the dashboard will produce a different first reflection in the interior space compared to dark-colored (e.g., black or blue) materials, linings, covers, or plastics of the dashboard. The same applies to the materials and colors of structured surfaces or interior trims in areas of the target surface that produce the first reflection.
[0031] Furthermore, the width of the test strip can vary for different dashboards. Therefore, the calibration method is not determined by a fixed background color or a fixed color scheme, but can be flexibly implemented in each vehicle to produce an optimized projection on the target surface individually.
[0032] A second test image for determining at least one target surface boundary of a target surface now has bars having a bar width that causes minimum brightness in the interior space and a brightness or color that causes maximum brightness in the interior space of the motor vehicle.
[0033] The target surface corresponds to a specific area of the vehicle, which can carry information or patterns, or signals or patterns, that can be projected onto said area. The determination of at least one target surface boundary results in an improved projection with enhanced clarity.
[0034] Calibration methods can be used to automate tolerance compensation in a simple and efficient manner, thereby reducing time and cost while improving calibration accuracy.
[0035] In this second test image, only the position of the bar is moved. This position can be overlapping, adjacent, or spaced apart from the second test image until the next second test image.
[0036] Within the scope of the invention, it may be advantageous to implement the target surface boundary defining the target surface on a first side and a second side of the target surface, wherein the second side is parallel or substantially parallel to the first side.
[0037] Therefore, the target surface boundary is determined on both sides. It is meaningful to first determine a first side of the target surface boundary and additionally determine a second side of the target surface, wherein the first side and the second side are arranged parallel to each other. Here, "substantially parallel" is understood as the second side having a deviation from the first side within the range of 0.1° to 5°, preferably 0.2° to 4°, more preferably 0.3° to 3°.
[0038] This results in a more accurate limitation of the target surface and thus allows for optimized projection of the image sequence onto the target surface. This is advantageous if the area of the target surface on the dashboard of a motor vehicle is uneven. Here, the projection planes on both sides can be limited to the target surface.
[0039] Within the scope of the invention, it is conceivable to implement a target surface boundary defining the target surface on a third side and a fourth side of the target surface, wherein the third side is parallel or substantially parallel to the fourth side, and wherein the third side and the fourth side are disposed perpendicular or substantially perpendicular to the first side and the second side.
[0040] Additionally, it is conceivable to implement target surface constraints on the third and fourth sides of the target surface. The third and fourth sides are arranged parallel or substantially parallel to each other. "Substantially parallel" is understood to mean that the fourth side has a deviation from the third side within the range of 0.1° to 5°, preferably 0.2° to 4°, more preferably 0.3° to 3°.
[0041] Naturally, the third and fourth sides are arranged perpendicularly or substantially perpendicularly to the first and second sides. "Substantially perpendicular" here is understood to mean that the third and / or fourth sides have an angle of 85° to 95°, preferably 86° to 94°, and more preferably 87° to 93° with the first and / or second sides.
[0042] This also improves the accuracy of the target surface boundary. Moreover, this is particularly advantageous for target surfaces that are not rectangular in shape. Where unevenness exists, it is absolutely advantageous to implement target surface constraints on the third and fourth sides.
[0043] Within the scope of this invention, the width of the test strip can be gradually changed from the maximum width to the minimum width, wherein the width is divided equally, preferably into three equal parts, and more preferably into four equal parts from the first level to the next level.
[0044] Therefore, the strip width can be determined with minimum brightness in the second reflection within the defined steps.
[0045] If the brightness stripe width is determined in the advanced calibration method, and the brightness is no longer determined after the immediately following equally divided stripe width, then the last detected brightness can be used as the minimum brightness. Alternatively, one could consider varying the reduction gradation between these two stripe widths to determine the stripe width that causes the minimum brightness.
[0046] This leads to an accurate and optimized strip width used to determine the surface constraints of the target surface.
[0047] Another option is to place the vehicle in a dark space before performing the first test sequence.
[0048] This dark space can be set, for example, at the end of a production line. During the calibration process, the darkness in this space reduces the scattering of light from the ambient light source in the first and second reflections. By placing the vehicle in the dark space, the reflection of the test image or test strip projected onto the projection surface is transmitted through the interior trim of the vehicle and perceived by the camera unit. Thus, the sharpness or colorfastness of the pattern or object immediately following the projection can be optimally displayed based on the corresponding interior trim characteristics when projected onto the target surface.
[0049] Alternatively, all lighting sources on the vehicle could be deactivated before the first test sequence is executed.
[0050] The shutdown of the vehicle's lighting sources, i.e., the disabling of interior lighting or warning indicators, further reduces scattered light within the vehicle. This also prevents interior scattered light, and only the reflection of the test image or test strip projected onto the projection surface is reflected by the interior trim within the vehicle's interior space and perceived by the camera unit. This further optimizes the determination of maximum and minimum brightness.
[0051] It is conceivable that the calculation unit of the control unit calculates the deviation between the projection of the projection unit and at least one target surface boundary of the target surface, and wherein the limiting unit limits, in particular scales or cuts the projection based on the deviation.
[0052] The limiting unit can therefore be predetermined based on the projection: how to handle an increased projection surface. It is also possible to consider deciding whether to scale or limit the projection based on calculated deviations.
[0053] Optionally, within the scope of this invention, a camera unit or an external camera unit may be used in the interior space of a motor vehicle.
[0054] The camera unit for detecting the first and second reflections can advantageously be located within the interior space of the vehicle, and this camera unit can also be used for other functions. For example, the camera unit can be used to identify passengers. Alternatively, an external camera unit may be used to determine the maximum brightness of the first reflection and the minimum brightness of the second reflection, wherein the external camera unit can, for example, be positioned in a dark space. The external camera unit here allows for the use of a camera with greater light sensitivity, thereby also enabling the determination of small brightness or differences in the first or second reflection.
[0055] A second aspect of the invention is a calibration system according to the invention for performing the calibration method according to any one of the preceding claims, comprising: a projection unit for projecting an image sequence and / or a first test image and / or a test strip and / or a second test image; a camera unit for detecting a first reflection, a second reflection, and a third reflection; and a control unit for adjusting and / or controlling the calibration system, wherein the control unit comprises: a calculation unit for calculating the maximum brightness of the first reflection and the minimum brightness of the second reflection, and a configuration of the maximum brightness with the brightness of the first test image and a configuration of the minimum brightness with the width of the test strip; and a limiting unit for limiting the second test image of the projection unit to at least one target surface boundary of the target surface.
[0056] This calibration system allows the projection surface to be limited to the target surface in automated methods and the aforementioned calibration methods.
[0057] It is conceivable that the control unit has a calculation unit for calculating the deviation between the projection of the projection unit and at least one target surface boundary of the target surface.
[0058] By using the calculated deviation, it can then be determined whether to scale or limit, that is, for example, cut the projection surface. Attached Figure Description
[0059] Further advantages, features, and details of the present invention arise from the following description, in which various embodiments of the invention are described in detail with reference to the accompanying drawings. Here, the features mentioned in the claims and specification may be individually or in any combination essential to the invention. The calibration method and calibration system according to the invention are further illustrated below with reference to the accompanying drawings. Schematic illustrations are provided respectively:
[0060] Figure 1 A perspective view of the calibration system is shown;
[0061] Figure 2 A schematic diagram of the calibration method is shown;
[0062] Figure 3 A schematic diagram showing the first projection of the first test image in the first test sequence;
[0063] Figure 4 A schematic diagram showing the second projection of the first test image in the first test sequence;
[0064] Figure 5 A schematic diagram showing the first projection of the test strip in the second test sequence;
[0065] Figure 6 A schematic diagram showing the second projection of the test strip in the second test sequence is shown;
[0066] Figure 7 A schematic diagram showing the first projection of the second test image in the determination of the target surface boundary;
[0067] Figure 8 A schematic diagram showing the second projection of the second test image in the determination of the target surface boundary.
[0068] Elements with the same function and mode of operation Figures 1 to 8 The same reference numerals are used for each of the attached figures. Detailed Implementation
[0069] exist Figure 1 The calibration system 50 is schematically shown in the diagram. It is used to perform 110. Figures 2 to 8One of the calibration methods 100 includes a calibration system 50 comprising: a projection unit 18 for projecting 120 image sequences and / or a first test image 20 and / or a test strip 34 and / or a second test image 36; and a camera unit 28 for detecting 130 a first reflection 24, a second reflection 35, and a third reflection 38. The camera unit 28 is disposed within the interior space 26 of the vehicle 16.
[0070] Furthermore, the control unit 32 is configured to adjust and / or control the calibration system 50, wherein the control unit 32 has: a calculation unit 30 for calculating the maximum brightness of the first reflection 24 and the minimum brightness of the second reflection 35, as well as the configuration of the maximum brightness with the brightness of the first test image 20 and the configuration of the minimum brightness with the strip width SB of the test strip 34; and a limiting unit 54 for limiting the second test image 36 of the projection unit 18 to at least one target surface boundary 40 of the target surface 12.
[0071] Additionally, the control unit 32 has a calculation unit 52 for calculating the deviation between the projection 10 of the projection unit 18 and at least one target surface boundary 40 of the target surface 12 as determined 140.
[0072] exist Figure 1 As can also be seen, the area projected by the projection unit 18 to the projection 10 is different from the area detected by the camera unit 28. The camera unit 28 detects the reflections from the first test image 20, the test strip 34, and the second test image 36 from the internal space 26, but does not detect the projection surface 22.
[0073] exist Figures 2 to 8 A calibration method 100 is shown for calibrating the projection 10 of an image sequence onto a target surface 12 of a dashboard 14 of a vehicle 16 by means of a projection unit 18. Figures 3 to 8 The first test sequence, the second test sequence, and various cases of determining the target surface boundary 40 of the target surface 12 are shown. For better display, in Figures 3 to 8 The text focuses on the function and omits the display of individual execution units.
[0074] The first test sequence, 110, is executed here. This first test sequence has the following steps:
[0075] - At least two first test images 20 are projected using the projection unit 18 - see Figure 3 and 4 — Project 120 onto the projection surface 22 of the instrument panel 14, wherein two first test images 20 are projected in full onto the projection surface 22, wherein the first test images 20 are projected sequentially, and each test image is assigned a brightness.
[0076] -During the execution of the first test sequence, the camera unit 28 detects 130 the first reflection 24 of each of the first test images projected 120 in the interior space 26 of the motor vehicle 16.
[0077] -The maximum brightness of 140 in the internal space 26 in one of the first reflections is determined by the calculation unit 30 of the control unit 32, and the maximum brightness is assigned to the brightness of one of the first test images 20 for use as the brightness in the second test sequence.
[0078] exist Figure 3 and 4 The different shadow lines of the projection 10 on the projection surface 22 represent different brightness levels of the projection 10. In this case, each shadow line corresponds to a different color of light from the light source. Furthermore, it is shown that the shadow lines in the interior space 26 are slightly weaker, which is caused by light scattering. The maximum brightness of the first reflection is therefore different in its light intensity from the brightness of the projection 10 itself.
[0079] Here, we have already calculated 140 by finding cell 30: Figure 3 The first reflection 24 has the maximum brightness. Therefore, with Figure 3 The second test sequence is performed using colored or shaded lines.
[0080] In the second test sequence, participants Figure 2 , 5 And 6, perform the following steps:
[0081] - Using projection unit 18, at least two test bars 34 with different widths SB are projected 160 onto projection surface 22 of instrument panel 14, wherein test bars 34 are projected 160 sequentially.
[0082] -During the second test sequence, the camera unit 28 detects the second reflection of each of the test strips 34 projected into the interior space 26 of the vehicle 16 for each of the test strips 34.
[0083] - The minimum brightness of 180 in the internal space 26 in one of the second reflections is determined by the calculation unit 30 of the control unit 32, and the minimum brightness is assigned to the strip width SB of one of the test strips 34 as the strip width SB for determining the target surface boundary 40.
[0084] For those with Figure 6 The minimum brightness of 180 in the internal space 26 is determined by the test strip 34 with a strip width SB. This strip width SB is then used to determine at least one target surface boundary 40 of the target surface 12.
[0085] At least one target surface boundary 40 of the target surface 12 is determined by the following steps, see [reference]. Figure 2 ,7 And 8:
[0086] - At least two, preferably at least three, more preferably at least four second test images 36 are projected 200 onto the projection surface 22 by means of the projection unit 18, wherein the second test images 36 are projected 200 sequentially, and each second test image 36 has a bar with a width SB in its edge region, the width of which has the minimum brightness of the second reflection.
[0087] -The camera unit 28 detects the third reflection 38 of the second test image 36 in the interior space 26.
[0088] -If the camera unit 28 detects 210 to the third reflection 38, then the target surface boundary 40 of the target surface 12 is obtained by means of the acquisition unit 30 of the control unit 32.
[0089] Here Figure 7 and 8 As can be seen, the bars in the two test images occupy different positions on projection plane 22. Here, in Figure 7 The second test image 36 was detected by camera unit 28 as the third reflection 38, but Figure 8 The bars in the second test image 36 are no longer identified as the third reflection 38, but rather as dark areas detected by the camera unit 28 in the interior space 26, indicated by the missing shadow lines in the interior space 26.
[0090] Therefore, in Figure 7 and 8 The boundaries or regions between the positions of the bars in the second test image 36 correspond to the target surface boundary 40.
[0091] Since the target surface boundary 40 is known, the second test image 36 of the projection unit 18 is restricted 230 to at least one target surface boundary 40 of the target surface 12 by means of the limiting unit 54 of the control unit 32 in order to perform calibration of the target surface 12.
[0092] As in Figures 3 to 8 As can be seen, the projection surface 22 protrudes or deviates on multiple sides of the target surface 12. The target surface boundary 40 has already been described above, defined on the first side 42 of the target surface 12. To improve the fit of the projection surface 22 to the target surface 12, the target surface boundary 40 of the target surface 12 is additionally implemented on a second side 44 of the target surface 12, wherein the second side 44 is parallel or substantially parallel to the first side 42. For this purpose, the stripes of the second test image 36 are arranged on opposite sides.
[0093] Additionally, a target surface boundary 40 of the target surface 12 is defined on the third side 46 and the fourth side 48 of the target surface 12, wherein the third side 46 is parallel or substantially parallel to the fourth side 48, and wherein the third side 46 and the fourth side 48 are arranged perpendicular or substantially perpendicular to the first side 42 and the second side 44. For this purpose, the strip of the second test image 36 is rotated by 90° so that the strip is arranged perpendicular to the test strip 34 of the second test image 36 to determine the target surface boundary 40 of the first side 42 and the second side 44.
[0094] As in Figure 5 and 6 As shown, different strip widths SB are used for test strip 34. Here, the strip width SB of test strip 34 is progressively increased from the maximum strip width SB ( Figure 5 Change to minimum bar width SB ( Figure 6 The width SB is divided equally from the first level to the next. Intermediate levels are not shown here.
[0095] To achieve optimized calibration, the vehicles were placed in a dark space before performing the first test sequence 110, and all lighting sources for the 250 vehicles 16 were also turned off.
[0096] To confine the projection surface 22 to the target surface 12, the calculation unit 52 of the control unit 32 calculates the deviation between the projection 10 of the projection unit 18 and at least one target surface boundary 40 of the target surface 12 as determined 140. Subsequently, the limiting unit 54 limits the size of the projection 10 onto the target surface based on this deviation, and as in Figure 8 The cut is shown in the image.
[0097] List of reference numerals
[0098] 10 projections
[0099] 12 target surfaces
[0100] 14 Dashboard
[0101] 16 motor vehicles
[0102] 18 projection units
[0103] 20 First test images
[0104] 22 projection planes
[0105] 24 First Reflection
[0106] 26 interior spaces
[0107] 28 camera units
[0108] 30 Units
[0109] 32 control units
[0110] 34 test strips
[0111] 35 Second Reflection
[0112] 36 Second test image
[0113] 38 Third Reflection
[0114] 40 Target Surface Boundary
[0115] 42 First side
[0116] 44 Second side
[0117] 46 Third side
[0118] 48 Fourth side
[0119] 50 Calibration System
[0120] 52 computing units
[0121] 54 restricted units
[0122] 100 Calibration Method
[0123] 110 execution
[0124] 120 Projector
[0125] 130 test
[0126] 140 requests
[0127] 150 execution
[0128] 160 projection
[0129] 170 tests
[0130] 180 requests
[0131] 190 confirmed
[0132] 200 projection
[0133] 210 test
[0134] 220 (request)
[0135] 230 limit
[0136] 240 placement
[0137] 250 is discontinued
[0138] SB bar width
Claims
1. A calibration method (100) for calibrating the projection (10) of an image sequence onto a target surface (12) of a dashboard (14) of a motor vehicle (16) by means of a projection unit (18) of a motor vehicle (16), the calibration method comprising the following steps: -Execute the first test sequence (110) using the following steps: ○ Using a projection unit (18), at least two, preferably at least three, more preferably at least four first test images (20) are projected (120) onto the projection surface (22) of the instrument panel (14). The at least two first test images (20) are projected (120) onto the projection surface (22) in their entirety. The first test images (20) are projected (120) sequentially, and each test image is assigned a brightness level. During the execution of the first test sequence, the camera unit (28) detects (130) the first reflection (24) of each of the first test images (20) projected (120) in the interior space (26) of the motor vehicle (16). ○ The maximum brightness (140) in the internal space (26) of one of the first reflections (24) is determined (140) by means of the determination unit (30) of the control unit (32), and said maximum brightness is assigned to the brightness of one of the first test images (20) for use as the brightness in the second test sequence. - Perform the (150) second test sequence using the following steps: ○ Using a projection unit (18), at least two, preferably at least three, more preferably at least four test strips (34) with different strip widths (SB) are projected (160) onto the projection surface (22) of the instrument panel (14), and the test strips (34) are projected (160) in sequence. During the second test sequence, the camera unit (28) detects (170) the second reflection (35) of each test strip (34) projected (120) in the interior space (26) of the motor vehicle (16). ○The minimum brightness of (180) in the inner space (26) of one of the second reflections (35) is obtained by means of the obtaining unit (30) of the control unit (32), and the minimum brightness is assigned to the strip width (SB) of one of the test strips (34) to be used as the strip width (SB) for determining the target surface boundary (40). - Determine at least one target surface boundary (40) of the target surface (12) by the following steps: ○ At least two, preferably at least three, more preferably at least four second test images (36) are projected (200) onto the projection surface (22) by means of a projection unit (18). The second test images (36) are projected (200) sequentially. Each second test image (36) has a strip with a width (SB) in its edge region. The width of the strip has the minimum brightness of the second reflection (35). ○The third reflection (38) of the second test image (36) in the interior space (26) is detected (210) by means of the camera unit (28). If the camera unit (28) detects (210) the third reflection (38), then the target surface boundary (40) of the target surface (12) is obtained (220) by means of the acquisition unit (30) of the control unit (32). - By means of the limiting unit (54) of the control unit (32), the second test image (36) of the projection unit (18) is limited (230) to the at least one target surface boundary (40) of the target surface (12) for the purpose of calibrating the target surface (12).
2. The calibration method (100) according to claim 1, characterized in that, Determining (190) the target surface boundary (40) of the target surface (12) is performed on the first side (42) and the second side (44) of the target surface (12), wherein the second side (44) is parallel or substantially parallel to the first side (42).
3. The calibration method (100) according to claim 2, characterized in that, The target surface boundary (40) of the target surface (12) is defined (190) on the third side (46) and the fourth side (48) of the target surface (12), wherein the third side (46) is parallel or substantially parallel to the fourth side (48), and the third side (46) and the fourth side (48) are arranged perpendicular or substantially perpendicular to the first side (42) and the second side (44).
4. The calibration method (100) according to at least one of the preceding claims, characterized in that, The width (SB) of the test strip (34) is gradually changed from the maximum width (SB) to the minimum width (SB), and the width (SB) is divided equally, preferably into three equal parts, and more preferably into four equal parts from the first level to the next level.
5. The calibration method (100) according to at least one of the preceding claims, characterized in that, Before performing the first test sequence (110), the vehicle is placed (240) in a dark space.
6. The calibration method (100) according to at least one of the preceding claims, characterized in that, Before performing the first test sequence (110), all lighting sources of the vehicle (16) are deactivated (250).
7. The calibration method (100) according to at least one of the preceding claims, characterized in that, The calculation unit (52) of the control unit (32) calculates the deviation of the projection (10) of the projection unit (18) from at least one target surface boundary (40) of the determination (140) of the target surface (12), and the limiting unit (54) limits, in particular scales or cuts the projection (10) in size based on the deviation.
8. The calibration method (100) according to at least one of the preceding claims, characterized in that, A camera unit (28) used in the interior space (26) of a motor vehicle (16) or an external camera unit (28).
9. A calibration system (50) for performing (110) the calibration method (100) according to any one of the preceding claims, said calibration system having: Projection unit (18) for projecting (120) image sequence and / or first test image (20) and / or test strip (34) and / or second test image (36). The camera unit (28) is used to detect (130) the first reflection (24), the second reflection (35), and the third reflection (38). A control unit (32) for adjusting and / or controlling a calibration system (50), the control unit (32) having: a determination unit (30) for determining (140) the maximum brightness of the first reflection (24) and the minimum brightness of the second reflection, as well as the configuration of the maximum brightness with the brightness of the first test image (20) and the configuration of the minimum brightness with the strip width (SB) of the test strip (34); and a limiting unit (54) for limiting the second test image (36) of the projection unit (18) to at least one target surface boundary (40) of the target surface (12).
10. The calibration system (50) according to claim 9, characterized in that, The control unit (32) has a calculation unit (52) for calculating the deviation between the projection (10) of the projection unit (18) and the at least one target surface boundary (40) of the target surface (12) as determined (140).